I don't know about you, but a bunch of my friends go to Youtube precisely because they can listen to pirated music. In fact, sometimes when I'm at parties, people pull up their own youtube playlists that are exactly the same content Grooveshark would have.

I also think Grooveshark's service has become less of a place for popular music consumption than indie/ self-made content because there are, quite frankly, much better options (ITunes, Spotify, Rdio) if you want to listen to your Billboard Top 100. And I think indie artists actually love having their content on Grooveshark. Grooveshark runs site-wide campaigns for new bands, they have a sweet bus that goes to concerts and records artists unplugged, and their radio service is very niche focused.